WiFi roam with band switch avoidance

Patent metadata

Field	Value
Publication number	US-12446018-B2
Application number	US-202318296193-A
Country	US
Kind code	B2
Filing date	Apr 5, 2023
Priority date	Apr 5, 2023
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A wireless device may use a 5 GHz frequency band to support both Wi-Fi and Bluetooth. The 5 GHz frequency band may be divided into two portions (e.g., high sub-band and low sub-band). A Wi-Fi module of the wireless device may perform a roam scan on a first sub-band to determine attempt to find a candidate channel that meets a target criteria. When the candidate channel that meets the target criteria is found on the first sub-band, the Wi-Fi module may join the candidate channel. If no acceptable candidate channel is found, the wireless device may perform a band switch protocol to allow the Wi-Fi module to preform a roam scan on a second sub-band.

First claim

The invention claimed is:

1. A method for a wireless device with a first transceiver and a second transceiver, the method comprising:
connecting the first transceiver to a first device via a first sub-band of a frequency band, and connecting the second transceiver to a second device via a second sub-band of the frequency band;
determining low signal quality for the first transceiver on a current channel of the first sub-band;
scanning, via the first transceiver, the first sub-band for a candidate channel that meets a target criteria;
when the candidate channel that meets the target criteria is found on the first sub-band, joining, via the first transceiver, the candidate channel; and
when the candidate channel that meets the target criteria is not found on the first sub-band:
performing a band switch protocol to cause the first transceiver and the second transceiver to switch sub-bands;
scanning, via the first transceiver, the second sub-band for the candidate channel that meets the target criteria on the second sub-band; and
joining, via the first transceiver, the candidate channel that meets the target criteria on the second sub-band.

2. The method of claim 1 , wherein performing the band switch protocol comprises:
sending a band switch request from the first transceiver to the second transceiver;
coordinating, via the second transceiver, with the second device to determine if the second device may be switched to the first sub-band; and
sending a band switch response from the second transceiver to the first transceiver.

3. The method of claim 1 , wherein the band switch protocol is not performed when the candidate channel that meets the target criteria is found on the first sub-band.

4. The method of claim 1 , wherein the first transceiver is a Wi-Fi transceiver and the second transceiver is a Bluetooth transceiver.

5. The method of claim 1 , wherein the frequency band is a 5 GHz band.

6. The method of claim 5 , wherein the frequency band is divided into a low sub-band and a high sub-band, wherein the low sub-band ranges from 5150 MHz to 5350 MHz, and the high sub-band ranges from 5470 MHz to 5850 MHz.

7. The method of claim 1 , wherein the target criteria comprises a signal strength threshold.

8. A wireless device comprising:
a first transceiver,
a second transceiver,
a processor; and
a memory storing instructions that, when executed by the processor, configure the wireless device to:
connect the first transceiver to a first device via a first sub-band of a frequency band, and connect the second transceiver to a second device via a second sub-band of the frequency band;
determine low signal quality for the first transceiver on a current channel of the first sub-band;
scan, via the first transceiver, the first sub-band for a candidate channel that meets a target criteria;
when the candidate channel that meets the target criteria is found on the first sub-band, join, via the first transceiver, the candidate channel; and
when the candidate channel that meets the target criteria is not found on the first sub-band:
perform a band switch protocol to cause the first transceiver and the second transceiver to switch sub-bands;
scan, via the first transceiver, the second sub-band for the candidate channel that meets the target criteria on the second sub-band; and
join, via the first transceiver, the candidate channel that meets the target criteria on the second sub-band.

9. The wireless device of claim 8 , wherein performing the band switch protocol comprises:
sending a band switch request from the first transceiver to the second transceiver;
coordinating, via the second transceiver, with the second device to determine if the second device may be switched to the first sub-band; and
sending a band switch response from the second transceiver to the first transceiver.

10. The wireless device of claim 8 , wherein the band switch protocol is not performed when the candidate channel that meets the target criteria is found on the first sub-band.

11. The computing apparatus of claim 8 , wherein the first transceiver is a Wi-Fi transceiver and the second transceiver is a Bluetooth transceiver.

12. The computing apparatus of claim 8 , wherein the frequency band is a 5 GHz band.

13. The computing apparatus of claim 12 , wherein the frequency band is divided into a low sub-band and a high sub-band, wherein the low sub-band ranges from 5150 MHz to 5350 MHz, and the high sub-band ranges from 5470 MHz to 5850 MHz.

14. The computing apparatus of claim 8 , wherein the target criteria comprises a signal strength threshold.

15. A non-transitory computer-readable storage medium, the computer-readable storage medium including instructions that when executed by a computer, cause the computer to:
connect a first transceiver to a first device via a first sub-band of a frequency band, and connecting a second transceiver to a second device via a second sub-band of the frequency band;
determine low signal quality for the first transceiver on a current channel of the first sub-band;
scan, via the first transceiver, the first sub-band for a candidate channel that meets a target criteria;
when the candidate channel that meets the target criteria is found on the first sub-band, join, via the first transceiver, the candidate channel; and
when the candidate channel that meets the target criteria is not found on the first sub-band:
perform a band switch protocol to cause the first transceiver and the second transceiver to switch sub-bands;
scan, via the first transceiver, the second sub-band for the candidate channel that meets the target criteria on the second sub-band; and
join, via the first transceiver, the candidate channel that meets the target criteria on the second sub-band.

16. The computer-readable storage medium of claim 15 , wherein performing the band switch protocol comprises:
sending a band switch request from the first transceiver to the second transceiver;
coordinating, via the second transceiver, with the second device to determine if the second device may be switched to the first sub-band; and
sending a band switch response from the second transceiver to the first transceiver.

17. The computer-readable storage medium of claim 15 , wherein the band switch protocol is not performed when the candidate channel that meets the target criteria is found on the first sub-band.

18. The computer-readable storage medium of claim 15 , wherein the first transceiver is a Wi-Fi transceiver and the second transceiver is a Bluetooth transceiver.

19. The computer-readable storage medium of claim 15 , wherein the frequency band is a 5 GHz band.

20. The computer-readable storage medium of claim 19 , wherein the frequency band is divided into a low sub-band and a high sub-band, wherein the low sub-band ranges from 5150 MHz to 5350 MHz, and the high sub-band ranges from 5470 MHz to 5850 MHz.

Assignees

• Apple Inc

Inventors

• Rana Shehla S
• Kumar Rajneesh
• Yu Yang

Classifications

• H04W88/06

  adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals · CPC title

• H04W72/0453 Primary

  Resources in frequency domain, e.g. a carrier in FDMA · CPC title

• H04W84/18

  Self-organising networks, e.g. ad-hoc networks or sensor networks · CPC title

• H04W84/12 Primary

  WLAN [Wireless Local Area Networks] · CPC title